Wax compositions and surface tension

ABSTRACT

Disclosed herein is a method of using surface tension to control the manufacture of candles until a surface tension ranging from 20 to 30 dynes/cm is achieved.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a national phase application of International Application No. PCT/US2018/029500, filed Apr. 26, 2018, entitled WAX COMPOSITIONS AND SURFACE TENSION, which claims the benefit of U.S. Provisional Patent Application No. 62/490,355, filed Apr. 26, 2017, entitled WAX COMPOSITIONS AND SURFACE TENSION, each of which is hereby incorporated by reference in its entirety.

FIELD OF THE INVENTION

This application relates to wax compositions comprising natural oils and using surface tension to control the purification of the wax composition or the formulation of a candle to improve candle properties.

BACKGROUND

Candles have been known and used for illumination since early civilization. The earliest candles are thought to have been developed by the Egyptians who soaked the pithy cores of reeds in molten tallow and to make rushlights or torches. The Romans are credited with developing the first candle which utilized a wick. The Romans also used tallow, derived from cattle or sheep suet, for candle wax. During the Middle Ages, beeswax was found to be suitable in candles. Beeswax candles were desirable over other candles because beeswax does not produce a smoky flame, or emit unpleasant odor when burned. Then, as now, beeswax candles were expensive, and prohibitively so, preventing most people from enjoying their advantages. Candles produced from molds first appeared in 15^(th) century France. Over the centuries, candle technology has refined and improved.

Today, more consumers are demanding candle wax formulations based upon natural materials, and more particularly plant-based oils. However, the production of candles from these formulations sometimes demonstrate cracking, air pocket formation, product shrinkage and a natural product odor associated with vegetable materials. Various soybean-based waxes have been reported to suffer performance problems relating to optimum flame height, effective wax and wick performance matching for an even burn, soot, maximum burning time, failure to achieve a consistent appearance upon resolidification after melting, product color integration and/or product shelf life.

Accordingly, there remains opportunity to improve the aesthetic and functional properties of natural oil wax formulations.

SUMMARY

Disclosed herein is a method of using surface tension to control the manufacture of candles until a surface tension ranging from 20 to 30 dynes/cm is achieved.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings, which are not necessarily drawn to scale, like numerals may describe similar components in different views. Like numerals having different letter suffixes may represent different instances of similar components. The drawings illustrate generally, by way of example, but not by way of limitation, various embodiments discussed in the present document.

FIG. 1 shows the relationship between surface tension and rate of consumption for a hydrogenated vegetable oil standard sample.

FIG. 2 shows the relationship between surface tension and rate of consumption for a hydrogenated vegetable oil standard sample that contains a surface tension modifier (siloxane).

DETAILED DESCRIPTION

The present application relates to natural oil wax compositions, specifically candle wax compositions and the use of surface tension to control the purification of the wax compositions to improve candle properties, for example rate of consumption, decrease potential interactions in formulations, and flame height, and improve consistency of said candle properties during the life of the candle.

As used herein, the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise. For example, reference to “a substituent” encompasses a single substituent as well as two or more substituents, and the like.

As used herein, the terms “for example,” “for instance,” “such as,” or “including” are meant to introduce examples that further clarify more general subject matter. Unless otherwise specified, these examples are provided only as an aid for understanding the applications illustrated in the present disclosure, and are not meant to be limiting in any fashion.

As used herein, the following terms have the following meanings unless expressly stated to the contrary. It is understood that any term in the singular may include its plural counterpart and vice versa.

As used herein, the term “natural oil” may refer to oils derived from plant or animal sources or byproducts from crude streams thereof. The term “natural oil” includes natural oil derivatives, unless otherwise indicated. Examples of plant-based oils include, but are not limited to, vegetable oils, algae oils, tall oils, derivatives of these oils, combinations of any of these oils, and the like. Representative non-limiting examples of plant-based oils include canola oil, rapeseed oil, coconut oil, corn oil, cottonseed oil, olive oil, palm oil, peanut oil, safflower oil, sesame oil, soybean oil, sunflower oil, linseed oil, palm kernel oil, tung oil, jatropha oil, mustard oil, camelina oil, pennycress oil, hemp oil, algal oil, and castor oil. Representative non-limiting examples of animal sources include lard, tallow, poultry fat, yellow grease, and fish oil. Tall oils are by-products of wood pulp manufacture. In certain aspects, the natural oil may be refined, bleached, and/or deodorized (also known as “RBD”) according to methods commonly known in the art.

As used herein, the term “natural oil derivatives” is synonymous with “modified natural oil” and refers to the compounds or mixture of compounds derived from the natural oil using any one or combination of methods known in the art. Such methods include but are not limited to saponification, transesterification, esterification, interesterification, hydrogenation (partial or full), isomerization, oxidation, polymerization, and reduction.

Wax Composition

The present wax compositions relate to waxes comprising natural oils and/or natural oil derivatives which can be used in candles. The waxes typically have a low paraffin content (less than 50%, and typically much lower amounts). The candles are typically formed from a natural oil or a natural oil derivative. Since the candles may be formed from a material with a low paraffin content and may be substantially devoid of paraffin (e.g. contain no more than about 0.5 wt. % paraffin), the candles are generally clean burning, emitting very little soot. The combination of low soot emission, biodegradability and production from renewable raw material makes the present waxes and candles particularly environmentally friendly products.

The present wax compositions are typically solid at room temperature, firm but not brittle, generally somewhat malleable, have no free oil visible and are particularly suited for use in forming many types of candles, such as container candles, votive candles, and pillar candles. The present waxes are also generally capable of providing consistent characteristics, such as appearance, upon cooling and resolidification (e.g., after being burned in a candle) of the melted wax. In addition, it is desirable that the wax composition is capable of being blended with natural color additives to provide an even, solid color distribution. It is also desirable that the wax composition is capable of being blended with other additives, such as perfumes or other fragrances, and preferably be capable of exhibiting good fragrance throw when the wax/fragrance blend is burned. It is further desirable that the wax composition is resistant to chalking and fat bloom.

Furthermore, the wax compositions of the present inventions are capable of having a surface tension that can be controlled, desirable burn properties (including both a desirable rate of consumption and flame height) and desirable glass adhesion properties.

In some aspects, the wax composition includes at least one of or a combination of glycerol monstearates and fatty acids. In some aspects, the wax composition includes a polyol fatty acid and/or fatty acid ester component (made up of partial and/or esterified polyols), for example triglycerides or transesterified or esterified derivatives. Very often the polyol fatty acid ester component has been subjected to an interesterification reaction, e.g., by treatment with a basic catalyst, such as a sodium alkoxide. For example the polyol ester component may include a polyol fatty acid ester component formed by a process which comprises interesterifying a polyol fatty acid ester precursor mixture. Due to their desirable melting characteristics, the polyol ester based waxes having a melting point of about 48° C. to about 75° C. can be particularly advantageous for use in forming candles. Commonly, the polyol ester based waxes include at least about 51 wt. % of a polyol fatty acid ester component (and more desirably at least about 70 wt. %). More typically, the wax includes at least about 51 wt. % of a esterified polyol ester component (e.g., a mixture of triacylglycerol compounds optionally combined with esters of other polyols), and preferably includes at least 70 wt. % of the esterified polyol. Very often, the esterified polyol ester component has been subjected to interesterification conditions. The interesterification of a mixture of polyol esters may be conducted on a mixture which also includes one or more polyol partial esters, e.g., a fatty acid monoglyceride and/or fatty acid diglyceride.

In some aspects, the wax composition includes other components such as a mineral wax, a free fatty acid, a solid natural wax (such as plant wax or insect wax), and/or other renewable resource based wax. These waxes are preferably present in the composition up to about 49 wt %, and often in much lower amounts. The mineral wax may be a petroleum wax such as a medium paraffin wax, a microcrystalline paraffin wax and/or a petroleum wax obtained from crude oil refined to other degrees. In another aspect, the wax composition includes no more than about 25 wt % of the alternate waxes. In still another aspect, the wax composition includes no more than about 10% by weight of the alternate waxes and may not contain an alternate wax at all.

In some aspects, the wax composition may include no more than about 5 to 15 wt % 16:0 fatty acids in its fatty acid profile, no more than about 10 wt % fatty acids having hydroxyl groups, and/or no more than about 25 wt % fatty acids having less than 16 carbon atoms or more than 18 carbon atoms. In other aspects, the wax composition may include at least about 51 wt % of the polyol fatty acid ester component, and preferably include at least about 51 wt % of a esterified polyol fatty acid ester component.

In some aspects, the wax composition comprises a combination of one or more of monoacylglycerols (MAGs), diacylglycerols (DAGs), and triacylglycerols (TAGs).

In some aspects, the wax composition can include between approximately 0.1-10 percent by weight TAGs, approximately 1-8 percent by weight TAGs, or approximately 2-5 percent by weight TAGs.

In some aspects, the wax composition can include between approximately 30-95 percent by weight MAGs and DAGs combined, approximately 40-80 percent by weight MAGs and DAGs combined, approximately 45-65 percent by weight MAGs and DAGs combined, or approximately 50-60 percent by weight MAGs and DAGs combined.

In some aspects, the wax composition can include between approximately 5-65 percent by weight MAGs, approximately 15-55 percent by weight MAGs, approximately 25-45 percent by weight MAGs, or approximately 30-40 percent by weight MAGs. In yet other aspects, the wax composition can include between approximately 1-50 percent by weight DAGs, approximately 5-35 percent by weight DAGs, approximately 10-30 percent by weight DAGs, or approximately 15-25 percent by weight DAGs.

In some aspects, the wax composition can include between approximately 0.1 percent by weight and approximately 65 percent by weight of a fatty acid. In another aspect, the wax composition can include between approximately 5 percent by weight and 60 percent by weight of a fatty acid. In another aspect, the wax composition can include between approximately 30 percent by weight and 50 percent by weight of a fatty acid. In yet another aspect, the wax composition can include between approximately 35 percent by weight and 45 percent by weight of a fatty acid.

In some aspects, the wax composition can include approximately 0.1-10 percent by weight TAGs; approximately 30-95 percent by weight MAGs and DAGs combined, and approximately 0.1-65 percent by weight fatty acid. In certain aspects, the wax composition comprises between 5-65 percent by weight MAGs and between 1-50 percent by weight DAGs.

In some aspects, the wax composition can include approximately 1-8 percent by weight TAGs, approximately 40-80 percent by weight MAGs and DAGs combined, and approximately 5-60 percent by weight fatty acid. In some aspects, the composition comprises between 15-55 percent by weight MAGs and between 5-35 percent by weight DAGs.

In some aspects, the wax composition has approximately 2-5 percent by weight TAGs, approximately 45-65 percent by weight MAGs and DAGs combined, and approximately 30-50 percent by weight fatty acid. In certain aspects, the wax composition comprises between 25-45 percent by weight MAGs and between 10-30 percent by weight DAGs.

In some aspects, the wax composition has approximately 2-5 percent by weight TAGs, approximately 30-40 percent by weight MAGs, approximately 15-25 percent by weight DAGs, and approximately 35-45 percent by weight fatty acid.

In some aspects, the wax composition comprises a high TAG content, wherein a majority of the wax, at least about 50 wt %, preferably at least about 75 wt %, and most preferably at least about 90 wt %, is a TAG component.

In some aspects, the wax composition comprises an at least partially hydrogenated natural oil having an Iodine Value ranging from about 45 to about 70, and more preferably from about 45 to about 55, and even more preferably from about 50 to 55, wherein Iodine Value (IV) is determined by the Wijs method (AOCS Cd 1-25).

In some aspects, the wax composition is a blend of partially hydrogenated soybean oil and fully hydrogenated palm oil, wherein the partially hydrogenated soybean oils makes up 70-90 wt % of the blend and hydrogenated palm oil makes up the remaining balance. In more preferred aspects, partially hydrogenated soybean oil makes up 80-85 wt % of the blend and hydrogenated palm oil makes up the remaining balance.

In some aspects, the wax composition primarily comprises paraffin and includes a minor amount of natural oil.

In some aspects, the wax composition has a solid fat content (measured at 10° C.) from about 80-100% (determined by AOCS Cd 16b-93) and in some aspects the solid fat content ranges from about 85-95%.

Achieving Desired Wax Composition and/or Finished Candle Formulation

There are many purification steps that can be incorporated in the process of manufacturing a candle wax composition utilizing natural oil and/or natural oil derivative as the starting material source. It shall be understood that such natural oils and derivatives inherently contain impurities and certain esterification, hydrogenation, etc., reactions that take place to achieve the candle wax composition described herein incorporate additional impurities that have a significant impact on candle wax formulations. Accordingly, there is a desire to control the concentration of these impurities completely or to a consistent level to improve the overall performance of the wax composition. Purification can be achieved through various methods commonly known in the art, for example chemical and/or physical refining, water washing, bleaching, deodorizing or filtration. As a person skilled in the art knows, each step has the objective of extracting impurities in the oil, for example but not limited to, phosphatides and solids, free fatty acids, metals (Ca⁺², Mg⁺², Fe⁺², Cu⁺², etc.), pigments, soaps, metals, steroids, nickel, pesticides tocopherols, sterol glucosides, sterol glucoside esters and phospholipids. These components are known to interfere with surface tension, accordingly the control or removal of which is desirable.

Described herein is a method of purifying the wax composition of the impurities described above via the utilization of surface tension to achieve a wax composition desirable for candle wax compositions. It shall be understood that surface tension can be used to control various methods of purification (refining, water washing, bleaching, deodorizing, fractionation, etc.), either upstream or downstream processing of the wax composition. In preferred aspects described herein, surface tension is utilized during filtration to control purification of wax compositions for candle wax applications.

As an example, the filtration process of a wax composition can utilize a filtration media with an affinity of absorbing and/or adsorbing certain impurity components. Preferred filtration media include silica-containing compositions such as commercially available Tri-Syl 100, Tri-Syl 300, or Oil-Dri Pure-Flo Perform 6000. In other aspects, the filtration media can include commercially available Microsorb 00/90, Magnesol, and Alumina 14-28 Mesh, for example.

To improve filtering performance, a filter aid can be used. A filter aid can be added to the oil directly and/or it may be applied to the filter. Representative examples of filtering aids include inorganic substrates such as diatomaceous earth, silica, alumina, and carbon. Typically, the filtering aid is used in an amount of about 10 wt % or less, for example, about 5 wt % or less, or about 1 wt % or less of the oil.

It shall be understood that filtration can include selective filtration as certain filtration medias and filtration aids are designed to remove unique impurities. Accordingly, the design of the filtration process will depend on the natural oil material being used as they each have unique impurity profiles. Furthermore, the desired rate of consumption and/or flame height properties of the candle wax composition can also influence filtration processing and which impurities are most important to control.

As one example of purification, the filtration step occurs at temperatures above the melting point of the wax composition and may optionally be ignited with an inert gas, for example but not limited to nitrogen, to reduce oxidation. Further, it shall be understood that in preferred aspects, the filtration takes place after the partial or full hydrogenation step; however, the filtration may also take place before the partial or full hydrogenation step.

In describing natural wax candle burn performance the rate at which wax is able to flow up the wick is critical. Affecting this rate are various parameters, e.g. viscosity, solids content, impurity profile and surface tensions. As most natural waxes are triglycerides of similar bulk chemical composition, the latter is greatly determined by the by miniscule amounts of natural surfactants present (impurity profile). It has been surprisingly found that the surface tension can be used as a unifying parameter not only for the control of wax manufacture but for the control of finished candle manufacture, i.e., it has been found that measured surface tension correlates highly with the burn performance regardless of triglyceride or non-natural wax bulk composition. Further, it is a simple and fast method well suited for the production environment.

Surface Tension

Aspects of the present invention includes a method using surface tension (as described herein, surface tension is measured using ASTM Method D1331-14, Method C, at a temperature of 70° C.) to control the manufacture of candles, including the purification of candle wax compositions and/or the finishing of the overall candle formulation, to improve candle properties and improve the consistency of said candle properties. An aspect of the present invention comprises purifying a modified natural oil and monitoring surface tension until a surface tension ranging from about 20 dynes/cm to about 30 dynes/cm is achieved. Another aspect of the present invention is formulating a candle and monitoring surface tension until a surface tension ranging from about 20 dynes/cm to about 30 dynes/cm is achieved.

Without being bound by any theory, controlling surface tension within this range provides insight on the desirable elimination or control of impurities that impact the burn performance of a candle. Furthermore, surface tension effectively measures miniscule amounts of contaminants that impact candle wax performance below the detection limit of other common methods, e.g., gas chromatography (GC) and high pressure liquid chromatography (HPLC). Further, the removal of volatile impurities in the oil such as, for example but not limited to, aldehydes, ketones and acids, phospholipids, sterol glucosides, natural surfactants, nickel, etc., which can contribute to odor, taste, color and significantly impact candle burn properties, can be controlled via surface tension. Accordingly, once the desired surface tension is achieved, it can be an indication that the desired wax composition or candle formulation has been achieved.

In some aspects, the surface tension can range between about 25 dynes/cm to about 30 dynes/cm. In some aspects, the surface tension can range between about 27 dynes/cm to about 30 dynes/cm. In some aspects, the surface tension can range between about 28 dynes/cm to about 30 dynes/cm. In some aspects, the surface tension can range between about 29.1 dynes/cm to about 30 dynes/cm, about 29.2 dynes/cm to about 30 dynes/cm, about 29.3 dynes/cm to about 30 dynes/cm, and 29.3 dynes/cm to about 29.9 dynes.

It shall be understood that in some aspects, the wax composition may comprise nickel that can be difficult to remove, as such nickel is usually in solution or in a finely divided state. The nickel content may be as high as 50 ppm and sometimes up to 100 ppm in nickel. These residual traces of nickel often occur in the form of soap and/or as colloidal metal. For various reasons, i.e. to prevent oxidation, it is desirable for the nickel content of the modified natural oil to be low, often below 1 ppm nickel. Also, the presence of nickel in a modified natural oil can have an effect on the burn performance of a candle (soot, height, size, rate, carbon heading, etc.). In certain aspects, the presence of nickel may affect the coloration and/or burn performance of candles made from the wax composition described herein by causing wick clogging, irregular flames and/or flame heights, poor fragrance interactions deleterious component (fragrance, surfactants, etc.) interactions, or a combinations of these issues

Accordingly, monitoring the various steps of the candle manufacturing process until the desired surface tension is achieved in combination with monitoring nickel content until both the desired surface tension is achieved and a nickel content less than 0.5 ppm, and in some aspects less than 0.2 ppm, and in some aspects less than 0.1 ppm, is achieved also provides improved rate of consumption and flame height properties for candles. While low nickel content is preferred, it shall also be understood as well that instances with high nickel content ranges, for example up to 50 ppm, can still provide desirable burn properties if surface tension is monitored and controlled within the above ranges.

Additionally, coupling the monitoring and control of surface tension with monitoring and controlling dissipation factor until both a dissipation factor (measured at 70° C. using ASTM method D924-08) ranging from about 0.0001 to about of 0.0600 and the desired surface tension is achieved also provides consistent candle burn properties, e.g., improved rate of consumption and flame height properties. In other aspects, monitoring and controlling all three properties simultaneously—surface tension, nickel content, dissipation factor—to achieve values within the articulated desired ranges for each property also provides improved burn performance, e.g., rate of consumption and flame height properties.

In some aspects, a near-infrared (“Near IR”) spectroscopy method with a partially squares algorithm can be used to accelerate the testing and monitoring of surface tension, nickel content, and/or dissipation factor as Near IR provides a rapid predication via correlation of prior Near IR and dissipation factor data (or other).

The various aspects described above, produce a candle wax composition having a rate of consumption (“ROC”) ranging from about 3 to about 4 grams per hour of burn and in preferred aspects, from about 3.25 to about 3.75 grams per hour of burn. Furthermore, the aspects produce a candle wax composition having a flame height ranging from about 0.25 inches to about 1.5 inches, more preferably from about 0.5 inches to about 1.5 inches, and even more preferably from about 0.5 inches to about 1.25 inches.

Additives to the Wax Composition

In certain aspects, the wax composition may comprise at least one additive selected from the group consisting of: wax-fusion enhancing additives, coloring agents, surface tension modifiers, scenting agents, migration inhibitors, free fatty acids, surfactants, co-surfactants, emulsifiers, anti-oxidants, additional optimal wax ingredients, and combinations thereof. In certain aspects, the additive(s) may comprise upwards of approximately 30 percent by weight, upwards of approximately 5 percent by weight, or upwards of approximately 0.1 percent by weight of the wax composition.

In certain aspects, the wax composition can incorporate a wax-fusion enhancing type of additive selected from the group consisting of benzyl benzoate, dimethyl phthalate, dimethyl adipate, isobornyl acetate, cellulose acetate, glucose pentaacetate, pentaerythritol tetraacetate, trimethyl-s-trioxane, N-methylpyrrolidone, polyethylene glycols and mixtures thereof. In certain aspects, the wax composition comprises between approximately 0.1 percent by weight and approximately 5 percent by weight of a wax-fusion enhancing type of additive.

In certain aspects, one or more dyes or pigments (herein “coloring agents”) may be added to the wax composition to provide the desired hue to the candle. In certain aspects, the wax composition comprises between about approximately 0.001 percent by weight and approximately 2 percent by weight of the coloring agent. If a pigment is employed for the coloring agent, it is typically an organic toner in the form of a fine powder suspended in a liquid medium, such as a mineral oil. It may be advantageous to use a pigment that is in the form of fine particles suspended in a natural oil, e.g., a vegetable oil such as palm or soybean oil. The pigment is typically a finely ground, organic toner so that the wick of a candle formed eventually from pigment-covered wax particles does not clog as the wax is burned. Pigments, even in finely ground toner forms, are generally in colloidal suspension in a carrier.

A variety of pigments and dyes suitable for candle making are listed in U.S. Pat. No. 4,614,625, the disclosure of which is herein incorporated by reference in its entirety. In certain aspects, the carrier for use with organic dyes is an organic solvent, such as a relatively low molecular weight, aromatic hydrocarbon solvent (e.g., toluene and xylene).

In other aspects, one or more perfumes, fragrances, essences, or other aromatic oils (herein “scenting agents”) may be added to the wax composition to provide the desired odor to the wax composition. In certain aspects, the wax composition comprises between about approximately 1 percent by weight and approximately 15 percent by weight of the scenting agent. The coloring and scenting agents generally may also include liquid carriers that vary depending upon the type of color- or scent-imparting ingredient employed. In certain aspects, the use of liquid organic carriers with coloring and scenting agents is preferred because such carriers are compatible with petroleum-based waxes and related organic materials. As a result, such coloring and scenting agents tend to be readily absorbed into the wax composition material.

In certain aspects, the scenting agent may be an air freshener, an insect repellent, or mixture thereof. In certain aspects, the air freshener scenting agent is a liquid fragrance comprising one or more volatile organic compounds, including those commercially available from perfumery suppliers such as: IFF, Firmenich Inc., Takasago Inc., Belmay, Symrise Inc, Noville Inc., Quest Co., and Givaudan-Roure Corp. Most conventional fragrance materials are volatile essential oils. The fragrance can be a synthetically formed material, or a naturally derived oil such as oil of bergamot, bitter orange, lemon, mandarin, caraway, cedar leaf, clove leaf, cedar wood, geranium, lavender, orange, origanum, petitgrain, white cedar, patchouli, lavandin, neroli, rose, and the like.

In other aspects, the scenting agent may be selected from a wide variety of chemicals such as aldehydes, ketones, esters, alcohols, terpenes, and the like. The scenting agent can be relatively simple in composition, or can be a complex mixture of natural and synthetic chemical components. A typical scented oil can comprise woody/earthy bases containing exotic constituents such as sandalwood oil, civet, patchouli oil, and the like. A scented oil can have a light floral fragrance, such as rose extract or violet extract. Scented oil also can be formulated to provide desirable fruity odors, such as lime, lemon, or orange.

In yet other aspects, the scenting agent can comprise a synthetic type of fragrance composition either alone or in combination with natural oils such as described in U.S. Pat. Nos. 4,314,915; 4,411,829; and 4,434,306; incorporated herein by reference in their entirety. Other artificial liquid fragrances include geraniol, geranyl acetate, eugenol, isoeugenol, linalool, linalyl acetate, phenethyl alcohol, methyl ethyl ketone, methylionone, isobornyl acetate, and the like. The scenting agent can also be a liquid formulation containing an insect repellent such as citronellal, or a therapeutic agent such as eucalyptus or menthol.

In certain aspects, a “migration inhibitor” additive may be included in the wax composition to decrease the tendency of colorants, fragrance components, and/or other components of the wax from migrating to the outer surface of a candle. In certain aspects, the migration inhibitor is a polymerized alpha olefin. In certain aspects, the polymerized alpha olefin has at least 10 carbon atoms. In another aspect, the polymerized alpha olefin has between 10 and 25 carbon atoms. One suitable example of such a polymer is a hyper-branched alpha olefin polymer sold under the trade name Vybar® 103 polymer (mp 168.degree. F. (circa 76.degree. C.); commercially available from Baker-Petrolite, Sugarland, Tex., USA).

In certain aspects, the inclusion of sorbitan triesters, such as sorbitan tristearate and/or sorbitan tripalmitate, and related sorbitan triesters formed from mixtures of fully hydrogenated fatty acids, and/or polysorbate triesters or monoesters such as polysorbate tristearate and/or polysorbate tripalmitate and related polysorbates formed from mixtures of fully hydrogenated fatty acids and/or polysorbate monostearate and/or polysorbate monopalmitate and related polysorbates formed from mixtures of fully hydrogenated fatty acids in the wax composition may also decrease the propensity of colorants, fragrance components, and/or other components of the wax from migrating to the candle surface. The inclusion of either of these types of migration inhibitors can also enhance the flexibility of the wax composition and decrease its chances of cracking during the cooling processes that occur in candle formation and after extinguishing the flame of a burning candle.

In certain aspects, the wax composition may include between approximately 0.1 percent by weight and approximately 5.0 percent by weight of a migration inhibitor (such as a polymerized alpha olefin). In another aspect, the wax composition may include between approximately 0.1 percent by weight and approximately 2.0 percent by weight of a migration inhibitor.

In another aspect, the wax composition may include an additional optimal wax ingredient, including without limitation, creature waxes such as beeswax, lanolin, shellac wax, Chinese insect wax, and spermaceti, various types of plant waxes such as carnauba, candelila, Japan wax, ouricury wax, rice-bran wax, jojoba wax, castor wax, bayberry wax, sugar cane wax, and maize wax), and synthetic waxes such as polyethylene wax, Fischer-Tropsch wax, chlorinated naphthalene wax, chemically modified wax, substituted amide wax, montan wax, alpha olefins and polymerized alpha olefin wax. In certain aspects, the wax composition may include upward of approximately 25 percent by weight, upward of approximately 10 percent by weight, or upward of approximately 1 percent by weight of the additional optimal wax ingredient.

In certain aspects, the wax composition may include a surfactant. In certain aspects, the wax composition may include upward of approximately 25 percent by weight of a surfactant, upward of approximately 10 percent by weight, or upward of approximately 1 percent by weight of a surfactant. A non-limiting listing of surfactants includes: silanes, siloxanes, polyether siloxane, alkyl siloxanes, polyoxyethylene sorbitan trioleate, such as Tween 85, commercially available from Acros Organics; polyoxyethylene sorbitan monooleate, such as Tween 80, commercially available from Acros Organics and Uniqema; sorbitan tristearate, such as DurTan 65, commercially available from Loders Croklann, Grindsted STS 30 K commercially available from Danisco, and Tween 65 commercially available from Acros Organics and Uniqema; sorbitan monostearate, such as Tween 60 commercially available from Acros Organics and Uniqema, DurTan 60 commercially available from Loders Croklann, and Grindsted SMS, commercially available from Danisco; Polyoxyethylene sorbitan monopalmitate, such as Tween 40, commercially available from Acros Organics and Uniqema; and polyoxyethylene sorbitan monolaurate, such as Tween 20, commercially available from Acros Organics and Uniqema.

In additional aspects, an additional surfactant (i.e., a “co-surfactant”) may be added in order to improve the microstructure (texture) and/or stability (shelf life) of emulsified wax compositions. In certain aspects, the wax composition may include upward of approximately 5 percent by weight of a co-surfactant. In another aspect, the wax composition may include upward of approximately 0.1 percent by weight of a co-surfactant. As described, surface tension can be used to control the manufacture of the candle wax composition and the finished candle formulation Furthermore, it shall be understood that surface tension modifiers can be used as necessary to further control or adjust surface tension during the manufacture of the candle wax composition or the finished candle formulation. Exemplary surface tension modifiers can include but are not limited to organomodified siloxanes such as the TEGOPREN® products (e.g., TEGOPREN® 5863, 5840, 6813, 5803). These surface tension modifier additives, when used, are commonly added in amounts less than 0.01 wt % of the wax composition.

EXAMPLES

All samples were prepared and measured following ASTM D1331-14, Method C-Surface Tension by Wilhelmy plate at a temperature of 70° C. to keep the samples in molten form.

Molten samples of partially hydrogenated vegetable oil were measured for surface tension.

See FIG. 1 for a comparison of partially hydrogenated vegetable oil compared against one with a nickel content greater than 0.2 wt %. See FIG. 2 for a comparison of partially hydrogenated vegetable oil compared against a partially hydrogenated vegetable oil treated with surface tension modifier, siloxane. Note the siloxane additive is present in amounts of 0.15 wt %, 0.1 wt %, 0.05 wt %, and 0.01 wt %, wherein the surface tension value increases as the siloxane additive amount decreases, respectively. FIG. 2 illustrates how surface tension modifiers can manipulate ROC. 

The invention claimed is:
 1. A method of making a candle wax composition, the method comprising: purifying a modified natural oil to provide the candle wax composition, the purifying comprising bleaching the modified natural oil, monitoring the surface tension of the candle wax composition, if the surface tension is outside of the range of from 20-30 dynes/cm, then further performing the purifying, and if the surface tension is in the range of from 20-30 dynes/cm, then providing the candle wax composition: wherein a candle comprising the candle wax composition has a different rate of consumption than an otherwise identical candle comprising the modified natural oil composition in place of the candle wax composition.
 2. The method of claim 1, wherein the purification is performed until the surface tension of the candle wax composition ranges from 29.1-30 dynes/cm.
 3. The method of claim 1, wherein the purification is performed until the surface tension of the candle wax composition ranges from 29.2-30 dynes/cm.
 4. The method of claim 1, wherein the purification is performed until the surface tension of the candle wax composition ranges from 29.3-29.9 dynes/cm.
 5. The method of claim 1, further comprising purifying the modified natural oil until the candle wax composition has a surface tension ranging from 20-30 dynes/cm and a nickel content less than 0.5 ppm.
 6. The method of claim 1, further comprising purifying the modified natural oil until the candle wax composition has a surface tension ranging from 20-30 dynes/cm and a nickel content less than 0.2 ppm.
 7. The method of claim 1, further comprising purifying the modified natural oil until the candle wax composition has a surface tension ranging from 20-30 dynes/cm and a nickel content less than 0.1 ppm.
 8. The method of claim 1, further comprising purifying the modified natural oil until the candle wax composition has a surface tension ranging from 20-30 dynes/cm and a dissipation factor ranging from 0.0001-0.0600.
 9. The method of claim 1, further comprising purifying the modified natural oil until the candle wax composition has a surface tension ranging from 20-30 dynes/cm, a dissipation factor ranging from 0.0001-0.0600, and a nickel content less than 0.5 ppm.
 10. The method of claim 1, wherein the rate of consumption of a candle comprising the candle wax composition ranges from 3-4 grams per hour.
 11. The method of claim 1, wherein the rate of consumption of a candle comprising the candle wax composition ranges from 3.25-3.75 grams per hour.
 12. The method of claim 1, wherein a candle comprising the candle wax composition has a flame height ranging from 0.25-1.5 inches.
 13. The method of claim 1, wherein the natural oil is selected from the group consisting of canola oil, rapeseed oil, coconut oil, corn oil, cottonseed oil, olive oil, palm oil, peanut oil, safflower oil, sesame oil, soybean oil, sunflower oil, linseed oil, palm kernel oil, tung oil, jatropha oil, mustard oil, camelina oil, pennycress oil, castor oil, or mixtures thereof.
 14. The method of claim 1, wherein purifying the modified natural oil comprises purifying a blend of the modified natural oil and paraffin, wherein paraffin is present in a majority amount.
 15. A method of forming a candle wax composition, the method comprising: finishing a candle wax composition comprising adjusting surface tension and dissipation factor of the candle wax composition until the surface tension ranges from 20-30 dynes/cm and until the dissipation factor ranges from 0.0001-0.0600, the adjusting of surface tension comprising adding a surface tension modifier to the candle wax composition, monitoring surface tension of the candle wax composition, and if the surface tension is outside of the range of from 20-30 dynes/cm, then further performing the adjusting of surface tension; wherein a candle comprising the pre-finished candle wax composition has a different rate of consumption than an otherwise identical candle comprising the finished candle wax composition in place of the pre-finished candle wax composition.
 16. The method of claim 15, wherein the finishing comprises adjusting the surface tension and a nickel content of the candle wax composition until the surface tension ranges from 20-30 dynes/cm and the nickel content is less than 0.5 ppm.
 17. The method of claim 15, further comprising wherein the finishing comprises adjusting the surface tension, the dissipation factor, and a nickel content of candle wax composition until the surface tension ranges from 20-30 dynes/cm, the dissipation factor ranges from 0.0001-0.0600, and the nickel content is less than 0.5 ppm.
 18. The method of claim 15, wherein the surface tension modifier is a siloxane additive. 